What is centreline?
It is important to note that the term ‘centre-line’ is often used by martial artists to describe the imaginary line down the centre of the body (running through the nose down past the navel); a useful way of remembering the important atemi (vital points) that lie along this line. For our purposes, we use centre-line to mean something completely different. We use centre-line in the context of balance.
The centre-line is an imaginary line that guides a jujitsoka to effect the optimum angle and direction for unbalancing their opponent. This can then be used as a core principle for attack/counter-attack (using your opponent’s centreline) and defence (protecting your own centreline). The concept of centreline is a core principle for JuJitsu, and should form the core of any student’s training. Moreover, its importance cannot be stressed enough, as not only can it be used for executing throws and takedowns, but also for delivering more effective strikes, locks, chokes and holds as well.
How to find the centreline
Imagine a line joining the heels of a person standing in a natural stance. Centreline crosses this halfway between the heels, forming a right angle in the process. Mathematically speaking, centreline is the perpendicular bisector of the line joining one heel to the other. By definition, this line is not impacted by rotation of hips, shoulders, arms or head, but rather by movement of the feet (more specifically the heel). Some examples of centreline are illustrated below for various stances (note centreline is marked in red).
You will notice that the arrows travel in two opposite directions. This is because a person can be unbalanced forwards or backwards along their centreline. Of course it is possible to unbalance someone by moving them across their line, however moving them along it will prove much more effective. This is a core principle within our teaching.